Limb Flex for Maxium Performance

[Shredd]

Got inspired to write this, looking at Buemaker's post on tillering his bow...  Thought it was important enough to have it's own thread...

  Listen up bowyers and bowyers to be...   This is a very important rule and it seems pretty self evident but we may not take it fully to heart...   It just really hit home for me in the last few bows I made and is critical for maximum performance... This applies to my bows and may apply to all bows...


                    ---- "Anything other than a consistent flowing bend will sap performance from your bow" ----


   Anotherwords the whole limb has to be working together equally...  Each part of the limb doing it's job in sync with the portion of limb next to it... Any deviation from this causes a weak link in the chain as the limb returns back to brace as it goes through the shot cycle causing a lack in performance...

  Any comments or thoughts to add to this are welcome...

[Roy from Pa]

Exactly, and that is why I tiller my bows for equal limb timing!

Been doing that for years..

[BMorv]

Shredd, I don't know much about performance in fiberglass bows, but most of the high performance wooden bows are designed to have stiff inners and stiff tips, minimizing the working limb and thus minimizing speed robbing vibration or histerisis.   
Even designing a bow this way where there's stiffer areas, it should be a smooth transition from non-working to barely working to really working.  Arc of the tiller or circular tiller shapes generally aren't going to be your fastest bows, because there's too much limb working increasing the changes for vibration in the limbs.
Us all wood bowyers can tell very easily if the wood is being overworked, and that is by monitoring set, or loss of weight through tillering.  Steve Gardner or Badger has developed a method called "no set tillering" and you should really check it out of you build all wood bows and want to minimize the set you are getting. Set will rob you of speed more than anything. 
Equal limb timing is another discussion.  I'm sure we can fill pages with these thoughts. 

[Forwardhandle]

You can put me in the bowyer to be catagorie Shreedy 😊 but some designs (highbrids) are like a combanation of 3 different bows in one and need to work in harmony between the different bows in the limbs but doesent always take the smooth arc of say a parallel limb bow but some how works together for superior performance in a given material ! I think stressing each bow in that limb to the maxium with a margin for durability and trying to maintain least amount of mass that will do it ,is always going to give you a great bow !

[Crooked Stic]

Got to agree with equal limb timing.

[Shredd]

Shredd, I don't know much about performance in fiberglass bows, but most of the high performance wooden bows are designed to have stiff inners and stiff tips, minimizing the working limb and thus minimizing speed robbing vibration or histerisis.   
Even designing a bow this way where there's stiffer areas, it should be a smooth transition from non-working to barely working to really working.  Arc of the tiller or circular tiller shapes generally aren't going to be your fastest bows, because there's too much limb working increasing the changes for vibration in the limbs.

 Great Point...   I don't do wood bows but I fully agree...  The same applies to glass bows...  That is where the tricks or difficulties come into play...  How stiff you make your limb bases and tips and how long you extend that stiffness can make or break a bow's performance... That's where the Magic, Alchemy (as I like to call it) and Knowledge & Experience of a bowyer comes into play...

You can put me in the bowyer to be catagorie Shreedy 😊 but some designs (highbrids) are like a combanation of 3 different bows in one and need to work in harmony between the different bows in the limbs but doesent always take the smooth arc of say a parallel limb bow but some how works together for superior performance in a given material ! I think stressing each bow in that limb to the maxium with a margin for durability and trying to maintain least amount of mass that will do it ,is always going to give you a great bow !

  Another Good Point...     A consistent bend can be very deceiving...  On a Hill style bow it is obvious but on a hybrid it can be deceiving with all the deflex and reflex built into the limb...  I do not have time now but I will post a pic of what I am talking about later on...

[Shredd]

  I got this pic off of POA...  It is a Centaur...  It appears to be bending a lot off the fades at full draw...  Or is it???  This bow shot just under 196 fps...   At 196 I doubt it is hinging... The unstrung and braced pics tell the whole story...

[Crooked Stic]

Got a ton of reflex and not much deflex. Be interesting to know the taper in those limbs.

[Forwardhandle]

That bow has a really nice string angle at FD !